Compressive Deformation Behavior of AlSi10Mg Lattice Structures Fabricated by Additive Manufacturing

Abstract

 This review focuses on the compressive mechanical properties of aluminum alloy lattice structures fabricated by laser powder bed fusion and discusses the deformation behavior of the lattice structures with various unit cell geometries. Three types of AlSi10Mg lattice structures consisting of body-centered cubic (BCC), truncated octahedral (TO), and hexagonal (Hexa) unit cells were fabricated and compression tests were conducted. The BCC and TO unit cell lattice exhibits shear bands during compression deformation. Therefore, the plateau region of the stress-strain curve is unstable and large stress fluctuations are observed. The relative modulus of elasticity（E^*/E_s）, relative yield strength（σ^*_y/σ_s） and plateau stress（σ_pl） of the lattice structures have a positive power-law relationship with the relative density（ρ^*/ρ_s）. The Hexa structural lattice showed no stress fluctuations in the plateau region. This is because the formation of shear bands, which cause stress fluctuations, was suppressed. However, contacts between neighboring struts were more likely to occur and the densification initiation strain became low. The BCC structure lattices had low plateau stresses. This is because the distribution of stress is not uniform within the lattice, with high stresses occurring in certain areas, causing large deformations in these areas.